** Shares of PhosCo PHO.AX fall 0.8% to A$0.066, set for their worst day since March 5, if losses hold

** The mineral resource explorer says it is undertaking a rights issue to raise A$5 million ($3.14 million)

** The issue price of A$0.05 per new share is at a 24.8% discount to the stock's last close

** Stock at its lowest level since March 6

** PhosCo stock down 5.7%, YTD

($1 = 1.5918 Australian dollars)

(Reporting by Adwitiya Srivastava in Bengaluru)

((Adwitiya.Srivastava@thomsonreuters.com))